Even Democrats who support President Obama’s choice for secretary of defense, Chuck Hagel, must have winced as the former Nebraska lawmaker — a Republican — appeared unable to respond with clarity and confidence to questions from his former GOP colleagues on the Senate Armed Forces Committee last week.

Hagel’s performance was in sharp contrast with the earlier Capitol Hill appearance by retiring Secretary of State Hillary Clinton who, when challenged by critics, had mounted a stirring, spirited defense of her performance. She was on her way out of the Obama administration while Hagel was trying to find his way in, and that made a huge difference.

One observer, Peter Beinart of The Daily Beast, has advanced the theory that Hagel’s surprisingly inept performance was actually the result of coaching by White House staffers who had strongly advised him not to react in his normal way — he has a reputation for having a short fuse — to the grilling he was sure to endure at the hands of Sens. John McCain, Lindsey Graham, James Inhofe and Ted Cruz.

“The problem is that Hagel is quite compelling when he’s mad,” Beinart observed. “I suspect that’s part of why Obama chose him in the first place, because Obama is himself mad that he was pressured by the military brass and by congressional Republicans into sending more troops to the lost cause that is the Afghan War. And Obama wants someone to push back, hard, if Benjamin Netanyahu and his friends in the GOP try to pressure him the same way on Iran.”

Whatever caused Hagel to appear unprepared for such an important confrontation, his performance was surely deeply disappointing to those who genuinely believe that the president needs a secretary of defense who has what it takes to stand up to the incredible pressures that are sure to come his way, especially at a time when our nation’s priorities are changing.

It is widely understood, for example, that Pentagon spending has to be reined in, and it is unlikely the generals will accept that without strong leadership from the secretary of defense.

But there are two things to understand about the Hagel nomination: First, despite his lackluster performance on Capitol Hill last week, he is almost certain to be confirmed. Second, as poor an impression as he may have made, the tone and nature of the questions thrown at him by his critics on the committee made them — Hagel’s critics — look more like immature schoolyard bullies rather than statesmen.

It was especially irksome to see McCain treat Hagel so rudely because when he ran for president in 2008, McCain said he’d appoint Hagel secretary of defense. They were once close friends.

There are enough (55) Democrats in the Senate to almost guarantee that, barring an unlikely Republican filibuster, Hagel will indeed become the next secretary of defense. Two Republican senators, Thad Cochran of Mississippi and Mike Johanns of Nebraska, have already declared their support for the appointment.

However, there are well-financed outside groups vigorously opposing the nomination for their own reasons and there will be great pressure exerted on senators by organizations such as The American Future Fund. Among their targets will be Democratic senators who face re-election in 2014, so look for an abundance of articulate anti-Hagel commercials on television between now and the vote on confirmation.

If indeed Hagel’s nomination is approved, it will be imperative that he immediately put his performance before the Senate committee behind him and demonstrate the judgment and leadership skills that earned him Obama’s trust in the first place.